Resource allocation for the multiple-access relay channels and OFDMA

Abstract

Within this article, the resource allocation problem for the multiple-access relay channel with orthogonal channel access is analysed. We propose a centralised optimisation framework that maximises the achievable sum rate of the network and that can be applied to a wide range of scenarios. We analyse different approaches to tackle the problem with individual transmit power constraints such as relaxing of constraints and splitting of the joint problem into a carrier allocation and individual power allocations. The carrier allocation deals with the exclusive assignment of subcarriers to different users, and the power allocation addresses the distribution of available power over assigned subcarriers. Several approaches are proposed for amplify and forward, decode and forward, and compress and forward strategies, and the performance as well as computational effort is evaluated by simulations. The obtained results suggest that the proposed algorithms can perform close to optimal.

Fairness Improvement in OFDMA Femtocell Networks

“…The Hungarian method is an algorithm which finds an optimal assignment for a given cost matrix. A combinational optimization algorithm known as Hungarian solves the assignment problem in polynomial time and is anticipated later primal dual methods [10].…”

“…In this paper, a joint subchannel and power allocation algorithm is introduced, which use Hungarian algorithm [10] for subchannel allocation and water filling [11] for power allocation. The Hungarian method is an algorithm which finds an optimal assignment for a given cost matrix.…”

DF-based sum-rate optimization for multicarrier multiple access relay channel

“…The setting that we consider is connected to [10] where the authors study the problem of resource allocation for a multiuser relay network with orthogonal channel access that uses OFDMA. They consider different relay strategies and maximize the sum-rate under individual power constraint.…”

“…The relay is half-duplex, implements the decode-and-forward protocol, and transmits only during the second transmission period. We propose a multicarrier transmission scheme based on OFDM where, in contrast to the OFDMA scheme [10], each subcarrier can be used by both sources simultaneously. In this paper, we refer to this scheme as OFDM for convenience.…”

QoS-Driven Energy-Efficient Resource Allocation in Multiuser Amplify-and-Forward Relay Networks

“…In recent years, cooperative communication has emerged as a promising way to enhance the reliability, coverage and performance of wireless communication systems [1]. The rapid growth of Internet-of-Things (IoT) in cooperative wireless communication has received considerable attention from the research community due to the hike in power dissipation costs, ecological, and environmental reasons, to emphasize on green wireless communications [2], [3].…”